| JP3763820 | BOLT AND BOLT INSTALLING METHOD |
| JP3568998 | Formwork member |
| US20130019549A1 | 2013-01-24 | |||
| US4202145A | 1980-05-13 | |||
| CN203066343U | 2013-07-17 |
| PATENT CLAIMS 1 . A permanent formwork arrangement for casting concrete slabs, which includes permanent formwork made from galvanized steel channels which are held together with pop rivets and/or by interlocking mechanisms and being adapted to span continuously and in two directions. 2. An arrangement as claimed in claim 1 , in which the channels form various sections. 3. An arrangement as claimed in claim 1 or claim 2, in which the channels are manufactured from galvanized (Z275) steel and/or mild/high tensile steel with a guaranteed yield stress of between 200Mpa to 550Mpa. 4. An arrangement as claimed in any one of the preceding claims, in which the channels are light weight steel. 5. An arrangement as claimed in any one of the preceding claims, in which the channels are manufactured by computerised cutting technology. 6. An arrangement as claimed in any one of claims 2 to 5, in which each section and/or channel is cut to the exact required length from a 3D drawing program. 7. An arrangement as claimed in any one of the preceding claims, in which holes for the rivets are pre-punched to form pre-punched channels. 8. An arrangement as claimed in claim 7, in which the pre-punched channels are adapted to be flat packed and delivered to site. 9. An arrangement as claimed in any one of claims 2 to 8, in which each section and/or channel is numbered for ease of assembly. 10. An arrangement as claimed in any one of claims 2 to 9, in which the sections and/or channels are assembled using pop rivets and/or hoop ties and/or corner strips and/or where required, self-tapping screws. 1 1 . An arrangement as claimed in any one of the preceding claims, in which the shape and size of the channels are adapted to make them easy to handle. 12. An arrangement as claimed in any one of the preceding claims, which, due to the compact form of the permanent formwork arrangement, is very stiff and light. 13. An arrangement as claimed in any one of the preceding claims, in which a 6 meter length of channel is adapted to be picked up and put in place by one person with great ease without the channel buckling or torsionally distorting. 14. An arrangement as claimed in any one of the preceding claims, in which side close-up elements are made from the same channels as the rest of the permanent formwork. 15. An arrangement as claimed in any one of the preceding claims, in which corner strips are made from channels cut in half. 16. An arrangement as claimed in any one of the preceding claims, in which, in the event that site dimensions do not match with what is ordered, the channels are adapted to be simply cut to size with a hand held grinder and reassembled. 17. An arrangement as claimed in any one of the preceding claims, which is adapted to enable a single person to set up an entire formwork deck alone without any assistance. 18. An arrangement as claimed in any one of the preceding claims, which is adapted so that the only tools required for the installation thereof include a hand held grinder, hand held drill, rivet gun, self-tapping screws, galvanised hoop ties and the channels. 19. An arrangement as claimed in any one of the preceding claims, in which the design of the permanent formwork arrangement is similar to that of a flat slab system, spanning in two directions and acting continuously over supports. 20. An arrangement as claimed in claim 19, in which the strong axis the channels act in conjunction with steel reinforcement to form the main span of the slab. 21 . An arrangement as claimed in claim 19 or claim 20, in which in the weak axis and over supports (hogging moment), the steel reinforcement is adapted to act alone. 22. An arrangement as claimed in any one of the preceding claims, which is adapted to enable two way spanning slabs due to the compression block that remains intact during hogging moments over supports. 23. An arrangement as claimed in any one of the preceding claims, which is adapted to be designed as a two way spanning flat slab continuous over supports in both directions. 24. An arrangement as claimed in any one of the preceding claims, in which the design thereof enables it to have a retail price which is 30% lower than other similar systems. 25. A permanent formwork arrangement for casting concrete slabs substantially as hereinbefore described with reference to the accompanying drawings. 26. A method for installing a permanent formwork arrangement for casting concrete slabs substantially as hereinbefore described with reference to the accompanying drawings. A method of casting concrete slabs substantially as hereinbefore described with reference to the accompanying drawings. |
FIELD OF INVENTION
The present invention relates to a permanent formwork arrangement.
More particularly, the present invention relates to a permanent formwork arrangement for casting concrete slabs.
BACKGROUND TO INVENTION
Formwork refers to either temporary or permanent moulds into which concrete or similar materials are poured. In the context of concrete construction, the falsework supports the shuttering moulds. The concept of permanent formwork has been widely used for some time all over the world, particularly in composite steel construction.
Currently companies manufacture permanent formwork out of bent galvanized steel plates. Unfortunately the known products do not have the ability to utilise the full section depth due to hogging moments over supports in both strong and weak axis. Hence they cannot be used or designed as a continuous 2-way spanning flat slab over supports in both directions. The existing products only promote one-way spanning slabs, usually only simply supported. This is due to the weakness of the hogging moment in the weak axis.
In addition the current products in the market are all wide and not easy to handle. Their width and shape makes them torsionally less stiff, which means they tend to twist over longer lengths and often require two people to be put in place. The assembly relies on an interlocking mechanism for ease of use but also often requires more than one person to assemble.
Sections are often sold in standard lengths and require cutting to fit site dimensions. Even if they are pre-cut the side close-up elements are of different shapes to that of the main spanning channels, which results in difficult adaptations if site measurements do not match what is delivered.
Current systems in the market advise that their systems be designed as simply supported, single spanning in the strong axis.
It is an object of the invention to provide a permanent formwork arrangement, which will assist overcoming the aforementioned problems.
SUMMARY OF INVENTION
According to the invention, a permanent formwork arrangement for casting concrete slabs includes permanent formwork made from galvanized and/or mild/high tensile steel channels which are held together with pop rivets and/or by interlocking mechanisms and being adapted to span continuously and in two directions.
The channels may form various sections.
The channels may be manufactured from galvanized (Z275) steel and/or mild/high tensile steel with a guaranteed yield stress of between 200Mpa to 55 Mpa.
The channels may be light weight steel. The channels may be manufactured by computerised cutting technology.
Each section and/or channel may be cut to the exact required length from a 3D drawing program.
Holes for the rivets may be pre-punched to form pre-punched channels. This does not exclude the possibility of having interlocking mechanisms/systems.
The pre-punched channels may then be flat packed and delivered to site.
Each section and/or channel is numbered for ease of assembly.
The sections and/or channels may then be assembled using pop rivets and/or hoop ties and/or corner strips and/or where required, self-tapping screws.
The shape and size of the channels may be adapted to make them easy to handle.
Due to the compact form of the permanent formwork arrangement, it may be very stiff and light.
A 6m length of channel may be picked up and put in place by one person with great ease without the channel buckling or torsionally distorting.
The side close-up elements may be made from the same channels as the rest of the permanent formwork.
Even the corner strips may be made from channels cut in half. In the event that site dimensions do not match with what is ordered, the channels are simply cut to size with a hand held grinder and reassembled.
The permanent formwork arrangement may be adapted to enable a single person may be able to set up an entire formwork deck alone without any assistance.
The permanent formwork arrangement may be adapted so that the only tools required may be a hand held grinder, hand held drill, rivet gun, self-tapping screws, galvanised hoop ties and the channels.
The design of the permanent formwork arrangement may be similar to that of a flat slab system, spanning in two directions and acting continuously over supports.
In the strong axis the channels may act in conjunction with steel reinforcement to form the main span of the slab.
Whereas in the weak axis and over supports (hogging moment) the steel reinforcement may act alone.
The permanent formwork arrangement may be adapted to enable two way spanning slabs due to the compression block that remains intact during hogging moments over supports.
Hence the permanent formwork arrangement may allow it to be designed as a two way spanning flat slab continuous over supports in both directions.
The design of the permanent formwork arrangement may enable it to have a retail price which is 30% lower than other similar systems. BRIEF DESCRIPTION OF DRAWINGS
The invention will now be described by way of example with reference to the accompanying schematic drawings.
In the drawings there is shown in:
Figure 1 : an image of a single person lifting a channel of the permanent formwork arrangement according to the invention;
Figure 2: a sectional side view showing the dimensions of the channel shown in
Figure 1 ;
Figure 3: an image of a typical lightweight steel construction utilising channels shown in Figure 2;
Figure 4: an image of the permanent formwork arrangements according to the invention;
Figure 5: a close-up image of the permanent formwork arrangements shown in
Figure 5;
Figure 6: a further close-up view of the permanent formwork arrangement shown in Figure 5;
Figure 7: an image depicting how the concrete is provided into the permanent formwork arrangement according to the invention; and Figure 8: a schematic diagram showing the advantage of the design of the permanent formwork arrangement of the invention in comparison to existing systems.
DETAILED DESCRIPTION OF DRAWINGS
Referring to the drawings, a permanent formwork arrangement, generally indicated by reference numeral 10, in accordance with the invention is shown.
The permanent formwork arrangement 10 for casting concrete slabs includes permanent formwork 12 made from galvanized steel channels 14 which are held together with pop rivets 16 and being adapted to span continuously and in two directions. This does not exclude the possibility of having interlocking m ech an i sm s/syste m .
The channels 14 form various sections.
The channels 14 are manufactured from galvanized (Z275) steel or mild/high tensile steel with a guaranteed yield stress of between 200Mpa to 550Mpa.
The channels 14 are of light weight steel.
The channels 14 are manufactured by computerised cutting technology.
Each section and/or channel 14 are cut to the exact required length from a 3D drawing program. Holes for the rivets 16 can be pre-punched to form pre-punched channels. This does not exclude the possibility of having interlocking mechanisms/system.
The pre-punched channels 14 are then be flat packed and delivered to site.
Each section and/or channel 14 is numbered for ease of assembly.
The sections and/or channels 14 are then assembled using pop rivets 16 and/or hoop ties 18 and/or corner strips 20 and where required, self-tapping screws.
The shape and size of the channels 14 can be adapted to make them easy to handle.
Due to the compact form of the permanent formwork arrangement 10, it is very stiff and light.
A 6m length of channel 14 can be picked up and put in place by one person with great ease without the channel 14 buckling or torsionally distorting.
The side close-up elements are made from the same channels 14 as the rest of the permanent formwork 12.
Even the corner strips 20 are made from channels 14 cut in half.
In the event that side dimensions do not match with what is ordered, the channels 14 are simply cut to size with a hand held grinder and reassembled.
The permanent formwork arrangement 10 is adapted to enable a single person to be able to set up an entire formwork deck alone without any assistance. The permanent formwork arrangement 10 is adapted so that the only tools required may be a hand held grinder, hand held drill, rivet gun, self-tapping screws, galvanised hoop ties and the channels.
The design of the permanent formwork arrangement 10 is similar to that of a flat slab system, spanning in two directions and acting continuously over supports.
In the strong axis the channels 14 act in conjunction with steel reinforcement 22 to form the main span of the slab.
Whereas in the weak axis and over supports (hogging moment) the steel reinforcement acts alone.
The permanent formwork arrangement 10 is adapted to enable two way spanning slabs due to the compression block that remains intact during hogging moments over supports.
Hence the permanent formwork arrangement 10 allows it to be designed as a two way spanning flat slab continuous over supports in both directions.
The design of the permanent formwork arrangement 10 enables it to have a retail price which is 30% lower than other similar systems.
The permanent formwork arrangement 10 according to the invention thus enables construction of a two storey building using light steel frame construction with concrete floors. The same versatile channels used for partitions and trusses can be used for the permanent formwork solution according to the invention.
This makes the system very adaptable.